Polyether polymer compounds as well as ion conductible polymer compositions and electrochemical devices using the same

ABSTRACT

The present invention is aimed to provide polyether polymers capable of improving an ion conductivity around room temperature as well as ion conductible polymer compositions and electrochemical devices using the same. The above objectives are achieved by using polyether polymers characterized by having the structure unit represented by the formula (1) and the structure unit represented by the formula (2) and/or the structure unit represented by the formula (3), and having polymeric and/or non-polymeric functional groups at each end of the molecular chains.

BACKGROUND OF INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to novel polyether polymercompounds as well as ion conductible polymer compositions andelectrochemical devices using the same.

[0003] 2. Description of the Related Art

[0004] Straight polyether, for example, polyethylene oxide has beenknown to exhibit ion conductance by dissolving an electrolytic salt.However, it does not satisfy a performance requirement as a material forion conductible polymer compositions due to its low ion conductance.

[0005] Thus, an effort to increase ion conductance has been attempted byusing polymers having side chains obtained by separately synthesizingmonomers capable of becoming side chains at polymerization andcopolymerizing the monomers.

[0006] The polyether having such side chains exhibits higher ionconductance than straight polyether, but its ion conductivity aroundroom temperature is still low and thus, improving this is to be theproblem.

[0007] The invention has been carried out in the light of the above, andprovides polyether polymers capable of improving an ion conductivityaround room temperature, as well as ion conductible polymer compositionsand electrochemical devices using the same.

SUMMARY OF THE INVENTION

[0008] The polyether polymer compounds of the invention are those havingthe structure unit represented by the formula (1) and the structure unitrepresented by the formula (2) and/or the structure unit represented bythe formula (3), and having polymeric functional groups and/ornon-polymeric functional groups at each end of the molecular chains.

[0009] One or more selected from the group consisting of (meth) acrylateresidues, aryl and vinyl groups can be used as the above polymericfunctional groups, and one or more selected from the group consisting ofalkyl groups with carbon atoms from 1 to 6 and functional groupscontaining boron atoms can be used as the above non-polymeric functionalgroups.

[0010] The ion conductible polymer compositions of the invention isthose containing one or two or more of the above polyether polymercompounds. Or, they are those containing one or more of the abovepolyether polymer compounds and an electrolytic salt. And a non-aqueoussolvent can be further contained in the ion conductible polymercomposition.

[0011] The above ion conductible polymer compositions include those inwhich the polyether polymer compounds are crosslinked.

[0012] Further, the electrochemical devices of the invention is obtainedby using any of the above ion conductible polymer compositions.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0013] 1. Polyether Polymer Compounds

[0014] The polyether polymer compounds of the invention are obtained byreacting ethylene oxide and 2,3-epoxy-1-propanol with the startingmaterial, or reacting 2,3-epoxy-1-propanol with ethylene glycol as thestarting material to yield a polymer compound followed by introducingpolymeric and/or non-polymeric functional groups at each end of abackbone and side chains in the resultant polymer compound.

[0015] The compounds having one or more active hydrogen resides andalkoxide can be used as the starting material.

[0016] Examples of active hydrogen residues for the compound having oneor more active hydrogen residues include hydroxyl group, preferablyhaving 1 to 5 active hydrogen residues. Specific examples of thecompounds having one or more active hydrogen residues includetriethyleneglycol monomethylether, ethyleneglycol, glycerine,diglycerine, pentaerythritol and their derivatives.

[0017] Also, specific examples of alkoxide include CH₃ONa, t-BuOK andtheir derivatives.

[0018] The polyether polymer compounds of the invention have thestructure unit represented by the formula (1) as well as the structureunit represented by the formula (2) and/or the structure unitrepresented by formula (3). The number of the structure unitsrepresented by formula (1) in one molecule is from 1 to 22800,preferably from 5 to 11400, and more preferably from 10 to 5700. Thenumber of the structure units of the formula (2) or (3) (but when bothare included, it is the total number) is from 1 to 13600, preferablyfrom 5 to 6800, and more preferably from 10 to 3400 as well as in onemolecule.

[0019] Examples of polymeric functional groups introduced at eachmolecular end include (meth) acrylate residues, allyl groups and vinylgroups, and examples of non-polymeric functional groups include alkylgroups or functional groups comprising boron atoms.

[0020] As the above alkyl groups, alkyl groups having 1 to 6 carbonatoms are preferable, ones having 1 to 4 carbon atoms are morepreferable, and methyl groups are especially preferable.

[0021] Examples of functional groups comprising boron atoms includethose represented by the following formula (4) or (5).

[0022] R¹¹, and R¹² in the formula (4) and R²¹, R²², and R²³ in theformula (5) may be identical or different, and each represents hydrogen,halogen, alkyl, alkoxy, aryl, alkenyl, alkynyl, aralkyl, cycloalkyl,cyano, hydroxyl, formyl, aryloxy, alkylthio, arylthio, acyloxy,sulfonyloxy, amino, alkylamino, arylamino, carbonamino,oxysulfonylamino, sulfonamide, oxycarbonylamino, ureide, acyl,oxycarbonyl, carbamoyl, sulfonyl, sulfinyl, oxysulfonyl, sulfamoyl,carboxylate, sulfonate, phosphonate, heterocyclic, —B(R^(a))(R^(b)),—OB(R^(a))(R^(b)) or OSi(R^(a))(R^(b))(R^(c)). R^(a), R^(b) and R^(c)each represents hydrogen, halogen, alkyl, alkoxy, aryl, alkenyl,alkynyl, aralkyl, cycloalkyl, cyano, hydroxyl, formyl, aryloxy,alkylthio, arylthio, acyloxy, sulfonyloxy, amino, alkylamino, arylamino,carbonamino, oxysulfonylamino, sulfonamide, oxycarbonylamino, ureide,acyl, oxycarbonyl, carbamoyl, sulfonyl, sulfinyl, oxysulfonyl,sulfamoyl, carboxylate, sulfonate, phosphonate, heterocyclic orderivatives thereof. R¹¹, and R¹² in the formula (4) and R²¹, R²², andR²³ in the formula (5) may bind together to form a ring, and the ringmay have substituents. Also, each group may be substituted withsubstitutable groups. Further, X⁺ in the formula (5) represents analkali metallic ion, and is preferably lithium ion.

[0023] The ends of molecular chains in the polyether polymer may be allpolymeric functional groups, all non-polymeric functional groups, or mayinclude both.

[0024] The average molecular weight (Mw) of the polyether polymercompound of the invention is not especially limited, but is usually fromabout 500 to 2 millions, and preferably from about 1000 to 1.5 millions.

[0025] 2. Ion Conductible Polymer Composition

[0026] The ion conductible polymer composition of the invention containsthe above polyether polymer compounds and an electrolytic salt, andfurther contains non-aqueous solvents if necessary.

[0027] The types of electrolytic salts are not especially limited, butlithium salts, ammonium salts, phosphonium salts such as (C₂H₅)₄PBF₄,salts of protonic acids such as sulfuric acid and perchloric acid, saltscontaining boron atoms and ionic liquid are able to be used.

[0028] Specific examples of lithium salts include LiPF₆, LiClO₄, LiAsF₆,LICF₃SO₃, LiN(CF₃SO₂)₂, LiN(C₂F₅SO₂)₂, LiC(CF₃SO₂)₃, LiCl, LiF, LiBr,LiI and derivatives thereof.

[0029] Specific examples of ammonium salts include (CH₃)₄NBF₄,(CH₃)₄NBr, (CH₃)₄NI, (CH₃)₄NClO₄, and (C₂H₅)₄NBF₄.

[0030] Examples of the salts comprising boron atoms include thoserepresented by the following formula (6):

[0031] wherein R³¹, R³², R³³, and R³⁴ in the formula (6) may beidentical or different, and each represents hydrogen, halogen, alkyl,alkoxy, aryl, alkenyl, alkynyl, aralkyl, cycloalkyl, cyano, hydroxyl,formyl, aryloxy, alkylthio, arylthio, acyloxy, sulfonyloxy, amino,alkylamino, arylamino, carbonamino, oxysulfonylamino, sulfonamide,oxycarbonylamino, ureide, acyl, oxycarbonyl, carbamoyl, sulfonyl,sulfinyl, oxysulfonyl, sulfamoyl, carboxylate, sulfonate, phosphonate,heterocyclic, —B(R^(a))(R^(b)), —OB(R^(a))(R^(b)) orOSi(R^(a))(R^(b))(R^(c)). R^(a), R^(b) and R^(c) each representshydrogen, halogen, alkyl, alkoxy, aryl, alkenyl, alkynyl, aralkyl,cycloalkyl, cyano, hydroxyl, formyl, aryloxy, alkylthio, arylthio,acyloxy, sulfonyloxy, amino, alkylamino, arylamino, carbonamino,oxysulfonylamino, sulfonamide, oxycarbonylamino, ureide, acyl,oxycarbonyl, carbamoyl, sulfonyl, sulfinyl, oxysulfonyl, sulfamoyl,carboxylate, sulfonate, phosphonate, heterocyclic or derivativesthereof. R³¹, R³², R³³, and R³⁴ in the formula (6) may bind together toform a ring, and the ring may have substituents. Also, each group may besubstituted with substitutable groups. Further, X⁺ represents an alkalimetallic ion, and is preferably lithium ion.

[0032] Specific examples of ionic liquids include pyridine, pyrimidine,pyridazine, pyrazine, triazine, oxazole, thiazole, imidazole, pyrazole,isooxazole, thiadiazole, oxadiazole, and quaternary salts of derivativesthereof substituted with substitutable groups.

[0033] A concentration of the above electrolytic salt is usually in therange of from 1 to 10000 parts by weight, preferably from 2 to 5000parts by weight, and more preferably from 5 to 2000 parts by weightbased on 100 parts by weight of the polyether polymer compound.

[0034] One or more selected from the group of non-proton solventsconsisting of carbonates, lactones, ethers, sulfolanes and dioxolanescan be used as the non-aqueous solvent.

[0035] A concentration of the electrolytic salt in the non-aqueoussolution dissolving the electrolytic salt in the above non-aqueoussolvent is usually in the range of from 0.01 mol/kg to 10 mol/kg, andpreferably from 0.02 mol/kg to 6.0 mol/kg.

[0036] The combining ratio of the above polyether polymer composition tothe non-aqueous solution is usually in the range of from 1/99 to 99/1(weight ratio, the same hereinafter), preferably from 1/99 to 50/50, andmore preferably from 1/99 to 30/70.

[0037] 3. Electrochemical Devices

[0038] The ion conductible polymer composition of the invention isapplicable for various electrochemical devices, and their examplesinclude lithium battery, solar battery with enhanced coloring matters,fuel battery, and condenser.

4. EXAMPLES

[0039] The invention is specifically described by examples below, butthe invention is not limited to the examples.

[0040] (1) Synthetic Example of the Polyether Polymer

Synthetic Example 1

[0041] (Synthesis of Compound 1)

[0042] In a pressure proof container, 9 g of KOH was added to 1 mol ofglycerine as a starting material, the temperature was elevated to 100°C., then the pressure was reduced to 5 mmHg or less of decompressiondegree via a vacuum pump, and subsequently the temperature was elevatedto 120° C. A monomer mixture obtained by mixing 20 mol of ethylene oxideand 20 mol of 2,3-epoxy-1-propanol was added thereto, and reacted at thetemperature range of 120±5° C.

[0043] After termination of the reaction, 23 mol of t-BuOK was added tothe pressure proof container, conduting alcoholation by elevating thetemperature to 120° C. and reducing the pressure to 5 mmHg or less ofdecompression degree via the vacuum pump, and subsequently cooled to 80°C. Further, 23 mol of methyl chloride was reacted at 80±50° C. Aftertermination of the reaction, excess acid was eliminated using anabsorbent, and subsequently conducting dehydration and filtrationafforded the polyether polymer modified at the ends.

Synthetic Example 2

[0044] (Synthesis of Compound 2)

[0045] In a pressure proof container, 9 g of KOH was added to 1 mol oftriethylene glycol as a starting material, the temperature was elevatedto 100° C., then the pressure was reduced to 5 mmHg or less ofdecompression degree via a vacuum pump, and subsequently the temperaturewas elevated to 120° C. A monomer mixture obtained by mixing 10 mol ofethylene oxide and 3 mol of 2,3-epoxy-1-propanol was added thereto, andreacted at the temperature range of 120±5° C.

[0046] After termination of the reaction, 3 mol of t-BuOK was added tothe pressure proof container, conducting alcoholation by elevating thetemperature to 120° C. and reducing the pressure to 5 mmHg or less ofdecompression degree via the vacuum pump, and followed by cooling toroom temperature. Further, 3 mol of Acryloyl chloride was added, andreacted at room temperature.

[0047] Separately, a boron compound was synthesized by reactingbiphenyl-2,2′-diol and borane at a molar ratio at 1:1 in dichloromethanewith ice-cooling and subsequently eliminating dichloromethane underreduced pressure. To the above reaction system, 2 mol of the boroncompound was added and reacted at room temperature. Excess acid waseliminated using an absorbent, and subsequently conducting dehydrationand filtration afforded the polyether polymer modified at the ends.

Synthetic Example 3

[0048] (Synthesis of Compound 3)

[0049] In a pressure proof container, 9 g of KOH was added to 1 mol ofethylene glycol as a starting material, the temperature was elevated to100° C., then the pressure was reduced to 5 mmHg or less ofdecompression degree via a vacuum pump, and subsequently the temperaturewas elevated to 120° C. Further, 10 mol of 2,3-Epoxy-1-propanol wasadded, and reacted at the temperature range of 120±5° C.

[0050] After termination of the reaction, 12 mol of CH₃OLi was placed inthe pressure proof container, conducting alcoholation by elevating thetemperature to 120° C. and reducing the pressure to 5 mmHg or less ofdecompression degree via the vacuum pump, and followed by cooling toroom temperature.

[0051] Separately, 1,1,1,3,3,3-hexafluoro-2-propanol and borane werereacted at a molar ratio at 3:1 in dichloromethane at room temperature.To the above reaction system, 6 mol of the product was added, andfurther 6 mol of acryloyl chloride was added, and reacted at roomtemperature. Purifying using the absorbent, and dehydrating andfiltrating afforded the polyether polymer modified at the ends.

Synthetic Example 4

[0052] (Synthesis of Compound 4)

[0053] In the pressure proof container, 1 mmol of CH₃ONa as a startingmaterial and 500 ml of dehydrated toluene were placed, and thetemperature was elevated to 100° C. A monomer mixture obtained by mixing1 mol of ethylene oxide and 0.6 mol of 2,3-epoxy-1-propanol was addedthereto and reacted at the temperature range of 100±5° C.

[0054] After termination of the reaction, 0.603 mol of t-BuOK wasdissolved in a 10-fold quantity of t-BuOH and placed in the pressureproof container to alcoholate, the temperature was elevated to 60° C.,and 0.603 mol of acryloyl chloride was reacted at room temperature.After termination of the reaction, purifying using the absorbent andeliminating the solvent under reduced pressure afforded the polyetherpolymer modified at the ends.

Synthetic Example 5

[0055] (Synthesis of Compound 5)

[0056] In the pressure proof container, 9 g of KOH was added to 1 mol oftriethyleneglycol monomethyl ether as a starting material, thetemperature was elevated to 100° C., then the pressure was reduced to 5mmHg or less of decompression degree via a vacuum pump, and subsequentlythe temperature was elevated to 120° C. A monomer mixture obtained bymixing 30 mol of ethylene oxide and 50 mol of 2,3-epoxy-1-propanol wasadded thereto, and reacted at the temperature range of 120±5° C.

[0057] After termination of the reaction, 30 mol of t-BuOK was added tothe pressure proof container, conducting alcoholation by elevating thetemperature to 120° C. and reducing the pressure to 5 mmHg or less ofdecompression degree via the vacuum pump, and followed by cooling to 80°C. Further, 20 mol of Butyl chloride was reacted at 80±5° C. and cooledto room temperature.

[0058] Separately, a boron compound was synthesized by reacting catecholand borane at a molar ratio of 1:1 in dichloromethane with ice-coolingand eliminating dichloromethane under reduced pressure. To the abovereaction system, 21 mol of the boron compound was added, and reacted atroom temperature. Further, 10 mol of acryloyl chloride was added andreacted at room temperature for 2 hours. After termination of thereaction, excess acid was eliminated using the absorbent, andsubsequently conducting dehydration and filtration afforded thepolyether polymer modified at the ends.

Synthetic Example 6

[0059] (Synthesis of Compound 6)

[0060] The polyether polymer modified at the ends was synthesized by thesame technique as that of Compound 4 except that the type and quantityof the compounds described in Table 1 were used.

Synthetic Example 7

[0061] (Synthesis of Compound 7)

[0062] The polyether polymer modified at the ends was synthesized by thesame technique as that of Compound 1 except that the type and quantityof the compounds described in Table 1 were used.

Synthetic Example 8

[0063] (Synthesis of Compound 8)

[0064] The polyether polymer modified at the ends was synthesized by thesame technique as that of Compound 1 except that the type and quantityof the compounds described in Table 1 were used.

Synthetic Example 9

[0065] (Synthesis of Compound 9)

[0066] The polyether polymer modified at the ends was synthesized by thesame technique as that of Compound 4 except that the type and quantityof the compounds described in Table 1 were used.

Synthetic Example 10

[0067] (Synthesis of Compound 10)

[0068] The polyether polymer modified at the ends was synthesized by thesame technique as that of Compound 4 except that the type and quantityof the compounds described in Table 1 were used. TABLE 1 Ethylene2,3-epoxy-1- Alcoholation Starting oxide propanol reagent Compound formodification of material (mol) (mol) (type/mol) the ends (type/mol)Compound 1 glycerine 20 20 t-BuOK/23 Methyl chloride/23 Compound 2Triethylene 10 3 t-BuOK/3 Acryloyl chloride/3 glycol2,2-biphenyldioleate borane/2 Compound 3 Ethylene 0 10 CH₃OLi/12Tris(1,1,1,3,3,3,- glycol hexafluoroisopropyl) borate/6 Acryloylchloride/6 Compound 4 CH₃ONa 1 0.6 t-BuOK/0.603 Acryloyl chloride/0.603(t-BuOH solution) Compound 5 Triethylene- 30 50 t-BuOK/30 Butylchloride/20 glycol Allyl chloride/10 monomethyl- Catecholate borane/21ether Compound 6 t-BuOK 22 6 t-BuOK/6.001 Propyl chloride/5 (t-BuOHsolution) Acryloyl chloride/1.001 Compound 7 Diglycerine 50 30 t-BuOK/34Hexyl bromide/32 Vinyl chloride/2 Compound 8 pentaerythritol 100 100t-BuOK/105 Methyl chloride/75 Allyl chloride/30 Compound 9 CH₃ONa 10 1t-BuOK/1.001 Ethyl chloride/0.2 (t-BuOH solution) Allyl chloride/0.801Compound 10 t-BuOK 2 13 t-BuOK/13.001 Methyl chloride/12.001 (t-BuOHsolution) Vinyl chloride/1

[0069] (2) Preparation and Evaluation of the Ion Conductible PolymerComposition

[0070] The polyether polymer compound of the invention is usable forelectrochemical devices with various intended uses utilizing theproperties of ion conductance. In the following examples and comparativeexamples, ion conductance of the ion conductible polymer compositionusing this polyether polymer compounds was evaluated using lithium saltas an electrolytic salt.

[0071] Ion conductance of the ion conductible polymer composition wasevaluated by making a film of 500 μm in thickness from each ionconductible polymer composition, punching out the film at 13φ which issandwiched with 2 sheets of lithium metal punched out at 13φ, measuringa resistant value of the ion conductible polymer composition at 20° C.by the complex impedance method, and estimating an ion conductivity fromthe resistant value.

Example 1

[0072] The ion conductible polymer composition of 500 μm in thicknesswas obtained by dissolving 2 g of Compound 1, 8 g of Compound 2, 2 g ofLiI and 0.1 g of AIBN in 1 g of acetonitrile, which solution was pouredbetween the glass plates, and subsequently drying under vacuum at 80° C.for 4 hours.

Examples 2 to 4

[0073] The ion conductible polymer composition was obtained as is thecase with Example 1 except that the type and quantity of the compoundsand salts described in Table 2 were used.

Example 5

[0074] The ion conductible polymer composition of 500 μm in thicknesswas obtained by mixing and dissolving 1 g of Compound 4, 2.7 g ofLi[CF₃SO₂)₂N], 9 g of y-butylolactone and 0.1 g of AIBN, which solutionwas poured between the glass plates, and subsequently leaving at 80° C.under an argon atmosphere for 2 hours.

Examples 6 to 8

[0075] The ion conductible polymer composition was obtained as is thecase with Example 5 except that the type and quantity of the compounds,salt and non-aqueous solvents in Table 2 were used.

Comparative Example 1

[0076] The ion conductible polymer composition was obtained as is thecase with Example 1 except that the type and quantity of the compoundand salt in Table 2 were used.

Comparative Example 2

[0077] The ion conductible polymer composition was obtained as is thecase with Example 5 except that the type and quantity of the compound,salt and non-aqueous solvent in Table 2 were used.

[0078] The type and quantity of the compounds, salts and non-aqueoussolvents as well as the ion conductivity in the above examples andcomparative examples are shown in Table 2.

[0079] The abbreviations for the non-aqueous solvents in Table 2 denotethe followings, respectively; GBL: γ-butylolactone, EC: ethylenecarbonate, DEC: diethylene carbonate, PC: propylene carbonate. TABLE 2Electrolytic salt Non-aqueous Ion Compound (type/quantity)(type/quantity) solvent (type/quantity) conductivity (S/cm) Example 1Compound 1/2 g + Compound 2/8 g LiI/2 g —   1 × 10⁻⁴ Example 2 Compound3/5 g + Compound 6/5 g LiBF₄/0.5 g —   3 × 10⁻⁴ Example 3 Compound 5/10g LiPF₄/3 g —   2 × 10⁻⁴ Example 4 Compound 8/10 g LiClO₄/1 g —   1 ×10⁻⁴ Example 5 Compound 4/1 g Li[CF₃SO₂)₂N]/2.7 g GBL/9 g 3.0 × 10⁻³Example 6 Compound 7/1 g LiBF₄/0.5 g EC/2 g + GBL/6 g 1.7 × 10⁻³ Example7 Compound 9/1 g LiPF₄/3 g EC/2 g + GBL/5 g + DEC/1 g 2.5 × 10⁻³ Example8 Compound 10/1 g LiClO₄/1 g PC/3 g + GBL/3 g 2.0 × 10⁻³ Comparative PEOwith molecular weight of Li[CF₃SO₂)₂N]/3 g —   9 × 10⁻⁷ Example 1150,000/10 g Comparative PEO with molecular weight of LiBF₄/1 g GBL/9 gIncapable Example 2 150,000/1 g measurement

[0080] The ion conductible polymer composition of the invention usingpolyether polymer(s) exhibits a high ion conductivity in roomtemperature and is suitably used for various electrochemical devicesusing ion conductible polymer compositions.

What is claimed is:
 1. A polyether polymer compound having the structureunit represented by the formula (1) and the structure unit representedby the formula (2) and/or the structure unit represented by the (3),characterized by having polymeric and/or non-polymeric functional groupsat each end of the molecular chains.


2. The polyether polymer compound according to claim 1, characterized inthat said polymeric functional group(s) is (are) one or more selectedfrom the group consisting of (meth) acrylate residues, allyl and vinylgroups, and said non-polymeric functional group(s) is (are) one or moreselected from alkyl groups of from 1 to 6 carbons and functional groupscontaining boron atoms.
 3. An ion conductible polymer compositioncontaining one or more polyether polymer compounds according to claim 1.4. An ion conductible polymer composition containing one or morepolyether polymer composition according to claim 1 and an electrolyticsalt.
 5. The ion conductible polymer composition according to claim 4,characterized by further containing non-aqueous solvent(s).
 6. The ionconductible polymer composition according to any one of claims 3 to 5,characterized in that said polyether polymer compounds are crosslinked.7. An electrochemical device using the ion conductible polymercomposition according to any one of claims 3 to 6.